How to play
Contourdle · a daily geography puzzle
Every day Contourdle shows one contour map with no labels. It's a single island, volcano or mountain somewhere on Earth. You have six guesses to name it, and every miss gives you more of the map.
01The rules
- The map shows one island, volcano or mountain, never a whole country. The label in the map's corner tells you which kind it is.
- Start typing a name and pick it from the list. Other common names work too, like Fuji or Rapa Nui.
- After a wrong guess you see how far away the answer is and in which direction. The locator map draws a ring at that distance.
- You get six guesses. A new sheet arrives every day at midnight UTC, and it's the same sheet for everyone.
- When the round is over, you can turn the map into a 3D view of the real terrain.
02What each miss reveals
The map starts sparse and fills in as you go:
- First look: just three contour lines.
- After one miss: all the contour lines.
- After two: elevation labels and a scale bar, so you know how high and how big it is.
- After three: the coastline and sea, if there is any, plus an elevation tint.
- After four: hillshading, which makes ridges and valleys stand out.
- After five: the region of the world it's in.
03How to read a contour map
A contour line joins points that are all at the same height above sea level. Walk along one and you'd never go up or down. Lines are drawn at regular steps of height, so the spacing between them tells you the shape of the ground.
- Lines close together mean steep ground: cliffs, crater walls, the flanks of a young volcano.
- Lines far apart mean gentle slopes or flat land, like plateaus, plains and wide valleys.
- Small closed rings are summits. Several rings nested inside each other are a peak.
- A closed ring that is lower than the ring around it is a hollow, such as a crater or caldera at the top of a volcano. The elevation labels tell you which way the ground goes.
- V shapes pointing uphill are valleys and stream beds. V shapes pointing downhill are ridges and spurs.
- The zero line is the coastline. On an island, every line closes into a loop around the land.
04Tips for guessing
- Volcanoes are often near-circular cones with even spacing all round, sometimes with a crater ring at the top. Big shield volcanoes are wide and gently sloped.
- Mountains in ranges tend to be long and ragged, with ridges branching off in many directions.
- Islands are easiest to read by their outline. Think about the shape of the coast before the height of the land.
- Use the distance and direction from a wrong guess. A miss of under 500 km means you're in the right neighbourhood.
05Questions
Is it free? Yes. There are no accounts, no ads and no cookies. Your games and stats stay on your device.
Where does the map data come from? The heights come from open elevation data, and the game draws the contours itself. The full credits are on the map data credits page.
Can I suggest a place? Please do. Use Suggest in the game to add a place or report a mistake.